1. Field
The present invention relates to a resin composition, a thiopyran-based squarylium compound and an image forming material.
2. Description of the Related Art
Conventionally, a resin composition and an image forming material each containing an infrared absorber are known.
For example, JP-A-2006-297954 (the term “JP-A” as used herein means an “unexamined published Japanese patent application”) discloses a thermal color transfer element comprising a substrate having deposited thereon, in order, (a) a light-to-heat conversion layer, (b) a color transfer layer, and (c) a transparent or translucent, thermally transferable infrared-sensitive adhesive topcoat containing an infrared absorber and a thermoplastic material.
For example, JP-A-2002-146254 discloses an infrared absorbing ink for invisible pattern formation, comprising an infrared absorber having a spectral absorption maximum wavelength at 750 nm to 1,100 nm, whose absorbance at 650 nm is 5% or less of the absorbance at the spectral absorption maximum wavelength.
For example, JP-A-2-118670 discloses a color toner for flash fixing, comprising a core containing a colorant in a binder resin and a cover part containing an infrared absorber in the same resin as the resin above and being provided around the core by heat fusion.
A production method of an infrared absorber is also known.
For example, JP-A-2001-011070 discloses a production method of a chalcogenopyrylium compound, using a compound of substituted acetylenes.